# I'm not familiar with the code and can't seem to resolve this error message, please help me **URL:** \ **Category:** I'm Stuck\ **Tags:** vps\ **Created:** [December 21, 2023, 5:25am UTC](https://community.nianticspatial.com/t/im-not-familiar-with-the-code-and-cant-seem-to-resolve-this-error-message-please-help-me/4166 "2023-12-21T05:25:02Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![Jae\_Hun\_Park](https://avatars.discourse-cdn.com/v4/letter/j/8491ac/32.png) [@Jae\_Hun\_Park](https://community.nianticspatial.com/u/Jae_Hun_Park)\ **Post date:** [December 21, 2023, 5:25am UTC](https://community.nianticspatial.com/t/im-not-familiar-with-the-code-and-cant-seem-to-resolve-this-error-message-please-help-me/4166/1 "2023-12-21T05:25:02Z")
_Include the following details (edit as applicable):_ - **Issue category** : Lightship Maps / Semantic Segmentation / Multiplayer / Real-time Mapping-Depth / ARDK Documentation / Unity Example Package / Sample App aka ‘AR Voyage’ / ARDK Virtual Studio Tools / Developer Tools / Networking / VPS / Scanning Framework - **Device type & OS version** : Android / iOS / Other Ex. iPhone 8+ on iOS 13 - **Host machine & OS version** : Mac / Windows / Linux / Other Ex. Mac on Big Sur x.x - **Issue Environment** : Unity Remote / Unity Mock / On Device / Dev Portal - **Xcode version** : - **ARDK version** : - **Unity version** : Description of the issue: I followed the documentation, installed ardk3, and tried to utilize a VPS and Location AR to locate content. I completed the follow along below and played in the Unity Editor, but got the error message below, what should I do? [How to Place Content in Real-World Locations Using Location AR] ![image](https://us1.discourse-cdn.com/niantic/original/2X/e/e7d855c9d322d6020a891a844fdf6987d5b20339.png) chatgpt4 is not helping me at all, please help. Error1. NullReferenceException: Object reference not set to an instance of an object Niantic.Lightship.AR.PersistentAnchors.ARPersistentAnchorManager.InitializeARPersistentAnchorManagerImplementation () (at ./Library/PackageCache/com.nianticlabs.lightship@7e30bd752f/Runtime/ARFoundation/Overrides/PersistentAnchors/ARPersistentAnchorManager.cs:350) Niantic.Lightship.AR.PersistentAnchors.ARPersistentAnchorManager.OnEnable () (at ./Library/PackageCache/com.nianticlabs.lightship@7e30bd752f/Runtime/ARFoundation/Overrides/PersistentAnchors/ARPersistentAnchorManager.cs:111) Niantic.Lightship.AR.LocationAR.ARLocationManager.OnEnable () (at ./Library/PackageCache/com.nianticlabs.lightship@7e30bd752f/Runtime/ARFoundation/Overrides/LocationAR/ARLocationManager.cs:181) Error2. NullReferenceException: Object reference not set to an instance of an object Niantic.Lightship.AR.PersistentAnchors.ARPersistentAnchorManager.TryTrackAnchor (Niantic.Lightship.AR.PersistentAnchors.ARPersistentAnchorPayload payload, Niantic.Lightship.AR.PersistentAnchors.ARPersistentAnchor& arPersistentAnchor) (at ./Library/PackageCache/com.nianticlabs.lightship@7e30bd752f/Runtime/ARFoundation/Overrides/PersistentAnchors/ARPersistentAnchorManager.cs:181) Niantic.Lightship.AR.LocationAR.ARLocationManager.TryTrackLocations (Niantic.Lightship.AR.LocationAR.ARLocation arLocations) (at ./Library/PackageCache/com.nianticlabs.lightship@7e30bd752f/Runtime/ARFoundation/Overrides/LocationAR/ARLocationManager.cs:449) Niantic.Lightship.AR.LocationAR.ARLocationManager.StartTracking () (at ./Library/PackageCache/com.nianticlabs.lightship@7e30bd752f/Runtime/ARFoundation/Overrides/LocationAR/ARLocationManager.cs:267) Niantic.Lightship.AR.LocationAR.ARLocationManager.Start () (at ./Library/PackageCache/com.nianticlabs.lightship@7e30bd752f/Runtime/ARFoundation/Overrides/LocationAR/ARLocationManager.cs:209) ---
**Author:** ![Jesus\_Niantic](https://avatars.discourse-cdn.com/v4/letter/j/b782af/32.png) [@Jesus\_Niantic](https://community.nianticspatial.com/u/Jesus_Niantic)\ **Post date:** [December 22, 2023, 10:46pm UTC](https://community.nianticspatial.com/t/im-not-familiar-with-the-code-and-cant-seem-to-resolve-this-error-message-please-help-me/4166/2 "2023-12-22T22:46:26Z")
Hello, Can you go to **Edit → Project** Settings and locate **XR Plug-in Management** ; it should be at the bottom. Click on **Niantic Lightship SDK** and to the right see if the **Enabled** box for **Persistent Anchors** is checked. If it’s not, please check the box and see if that works. If it is already checked let me know to see what else I can suggest ---
**Author:** ![Maverick\_Niantic](https://avatars.discourse-cdn.com/v4/letter/m/8edcca/32.png) [@Maverick\_Niantic](https://community.nianticspatial.com/u/Maverick_Niantic)\ **Post date:** [March 5, 2026, 11:20pm UTC](https://community.nianticspatial.com/t/im-not-familiar-with-the-code-and-cant-seem-to-resolve-this-error-message-please-help-me/4166/3 "2026-03-05T23:20:32Z")